In patients with heart failure, one month of moderate exercise significantly improves heart function and aerobic capacity and at least partially ameliorates symptoms of poor heart function, results of a study indicate.

Dr. Stephen F. Crouse from Texas A&M University in College Station presented the study Tuesday at the annual meeting of the American Physiological Society, part of the Experimental Biology 2008 scientific conference underway in San Diego.

The study involved 68 women and 298 men with heart failure who were referred to the Center for Cardiovascular Rehabilitation in Bad Schallerbach, Austria, for four weeks of residential cardiac rehabilitation to improve heart function.

The subjects rode a stationary bicycle six times a week for between 14 and 22 minutes, depending on the individual patient's maximal working capacity at the start of the program. They also took a brisk 45-minute walk daily, working at 60% to 70% of their maximal heart rate.

At the end of the four weeks, patients performed on average 18% better on the stationary bike, with a significant 12% increase in maximal oxygen uptake (VO2max). They also experienced significant decreases in resting heart rate and blood pressure.

Furthermore, Dr. Crouse told Reuters Health, "Only 25 days of exercise training as part of a residential cardiac rehabilitation program reduced NT-proBNP, indicating an improvement in heart muscle function. This reduction in NT-proBNP coincided with an increase in maximal working capacity and in cardiovascular function."

These "encouraging" findings, Dr. Crouse and colleagues wrote in a meeting abstract, "suggest a relatively powerful effect of short-term exercise training as part of a residential cardiac rehabilitation program to improve myocardial function and to at least partly ameliorate the symptoms of ventricular systolic and diastolic insufficiency."

These data, Dr. Crouse added, suggest that the serial measurement of NT-proBNP represents a "sensible marker for myocardial improvement in cardiac patients undergoing cardiovascular rehabilitation and may be used to document the progress of recovery."